Reenforced concrete dam



July28, 1931. H. soRE-NSEN l REENFORCED CONCRETE DAM Filed May 13, 1929 fg, #15g/291g fondi/M565 llvm g :QQ/5gg,

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INVENTOR 1 Patented July 28, 1931 HENRY SORENSEN, OF SAN FRANCISCO, CALIFORN BEENFORCED CONCRETE DAM VApplication filed May 13, 1929. Serial No. 362,704.

yMy invention consists of strut members, which are adapted to hold the initial tension that is imparted, by suitable means, into the reinforcements that .are anchored to a base or foundatiomuntil the concrete has set into cohesion with the initially tensioned reinforcements. My invention may also be used for any other reenforced concrete structures for which it is adapted. y

I have described my invention in the following specification andy the accompanying drawings. i i

` In the drawings .Fig 1 illustrates part of the base of the f unit of a dam, with my invention placed upon said base and ready to receive the concrete for said unit, and Fig. 1 also illustrates a fragment of said unit completed.

Fig! 2 illustrates any enlargement of the tensioning device, which may, however, be designed in'any other'useful way.y

Fig. 3 illustrates an enlargement of the reinforcement connecting member, instead of which', however, any other useful device may be used. l

Fig. 4 illustrates an enlargement of the tensioning device connected up with the reinforcement, and also 'shows the reinforcements connected together by their connecting member. i Y

Fig. 5 illustrates a fragment of the lower part of the above referred to unit in a completed condition, with my invention placed thereupon ready to receive the concrete for its upperfpart.` y v ,Fig. 6 illustrates a modied construction ofmy invention. f ,v

Fig.' 7 is a reduced section taken at 7-7 on Fig. 6.

Similar numerals designate similar parts.

Numeral 1y designates anchors which are attached to base 2 ofunit 4.. 3 designates the tensioning device. 4 is part of a unit of the dam. 5 are strut members. 6 are the reinforcements. 7 are reinforcement connections. 8 arevbeams. 9 are bolts. 10 are'washers. 11 are nuts. 12 are openings in connections 7. 13 are other openings in connections 7. 14 are wedges. 15 is the concrete. '16 are lianges, or corrugations, on reinfo 1cements 6. 17 are casings.

In Fig. 1 I have illustrated my invention applied to a fragment of the firstor lower part of unit el of the dam, and I embed anchors 1 into its base 2, letting the upper ends of anchors 1 extend somewhat above base 2. I place tensioning device 3, by means not shown, at a suitable distance above the point, to where I intend to pour the concrete for unit Ll, and I place strut members 5 upon base 2, letting the upper ends of strut members 5 contact the lower part of tensioning device 3. l/Jhile any other suitable material may be used, I have shown concrete, as the material out of which I construct strut members I now connect the upper ends of stub rein forcement-s 6 with tensioning device 3, in a manner which I will describe below, and at tach the lower ends of said stubs 6 to the upper ends of suitable lengths of other reinforcements 6, by means of connections 7, and connect the lower ends of said other reinforcements 6 with the upper ends of anchors 1, likewise'by means of connections 7. trut members 5, as well as reinforcen'ients (i, extend from base 2 into the space, which is occupied by unit 4:1 In Fig.` 2 I have shown an enlarged illustration of tensioning device 3, and the .f'arious parts of which device 3 is composed. These part-s consist of suitably spaced beams 3, which are held together by means of bolts 9. Upon the top flanges of beams 3 I place washers 10, and upon the top of washers l() I place nuts 11.

In Fig. 3 I have shown an enlargement of connections 7, which consist of elongated steel boxes having openings 12 on all four r sides, through which concrete 1e may flow, H

and the tops and bottoms of connections l' are furnished with inwardly slanting openings 13, against which wedges 14 can operate. The middle of wedges 14 have grooves, in their vertical direction, adapted to grip reinforcements 6. The arrows indicate the direction of the tension, which is imparted into reinforcements 6 and when said tension' is applied wedges 14 will become squeezed against the slanting` sides of opening 13, and

hold reinforcements 6 firmly to connections 7. The grip, which wedges 14 have upon reinforcements 6, will increase in proportion to the tension which is applied to reinforcements 6, due to the wedge action of 14 against 13. Reinforcements 6 are attached in the same manner to 1. i

In Fig. 4 I have shown an enlarged illustra.-

tion of reinforcements 6 attached to tensioning device 3, as well as to connections 7; The top part of stub reinforcement 6 is threaded to fit nut 11. Stub 6 is placed, from below, between the pair of beams 8, through washer 10, and screwed into nut 11, and the lower part of stub 6 is connected to other reinforcements 6, by means of connections 7, inthe same manner as above described. I prefer to use .stubs of reinforcements 61y to connect up to tensioning device v3, and use the same stubs 6 for the various parts of units 4 as they go up, in order to avoid the expense of having to cut threads innew reinforcements 6 every time a part is added to a unit 4.

Strut members 5 extend between, and contact, base 2 and the lower flanges of'beams 3,

of the tensioning device 3, and when the ten-y sion is applied to reinforcements 6, by tightening nuts 11, strut 5 will prevent any defiection ofthe tensioning device 3, and thereby hold the tension, which tensioning device 3initially imparts into reinforcements 6.

In Fig. 1 I have also illustrated afragment of the first, or lower, finished part. of unit 4, showing the upper part of a concrete strut member 5 extending above this fragment of the lower finished part of unit 4, while the other part of said concrete strut 5 has become an integral part of concrete 15 in said lower part. of unit 4. The initiallytensioned reinforcements 6 are shown embedded in Concrete 15 of the fragment of said lower part o-f unit 4. i

Due to the fact that strut members 5 hold the tension, which is imparted into reinforcements 6 by tensioning device 3, said initial tension is maintainedl while concrete 15 sets into cohesion with reinforcements 6.

While the design of reinforcements 6' may consist of any known and useful type, I .prefer to supply reinforcements 6 with flanges, or corrugations, 16, whereby concrete 15 is given an added grip upon reinforcements 6,

besides the hold, which concrete 15 has upon reinforcements 6, duel to the cohesion between l5 and 6. After concrete 15 has setinto cohesion with reinforcements 6, tensioning device 3 is removed for use in the upper part of unit 4. l

InA Fig. 5 I have illustrated the lower part of the fragment of unit 4 finished,A with reinforcements 6, concrete strut 5 and tensioning device 3 placed in their respective positions -upon the top of said lower iinished fragment of unit 4, ready to receive the concrete for. the upper part of said unit 4. Struts 5,- in

of connections 7, are attached to those lower rein'forcements.6l that extend above the lower part of unit 4, will have the same grip upon the lowery reinforcements 6, as those lower reinforce1nentsf6 have upon anchors 1.

In the manner which I have described the units 4 stand side byy side, but these units 4 may also be placed one on the top o-f the other, whenever that may bedesired. "i

When the upper part of unit V4 is com,-

pleted', I may leave tensioning,device 3,

besides concrete strutmembers 5 'embedded in concrete 15;.but in such case concrete 15 must first be poured flush with washers 10, and there first allowed to set, so that nuts 11 may'fhst be loosed,.before nuts 11 are ein-bedded by concrete 15., I do that in order to transfer the strut action, which members 5 exercise upon steel 6, overto 4CoIlCIete 15 after concrete 15 has become hard.Y The dotted lines, on Fig. 5 indicate how concrete 15,. will embed tensioning; device 3, when this modification of the structure yis completed.

In 6 and Fig. 7 IV have 'shown' strut members .5 made-of a materialrvihich is not found advisable to leave embedded inl concrete 15. In suchcase I provide strut inembers 5 with casi'ngs 17. These casings-V 17 isolate strut members 5 from the concrete 15. After concrete 15 has set into hard cohesion with the initially tensioned reinforcements 6, in the same manner as I have previously described-,I first remove tensioning device 3', and there-upon extract strut members 5 from casings 17. 'After that is done I remove casings 17 and then fill the openings (which are left by casings 17) with concrete l5. Fig. 7V is Fig 6s section at 7 7.

No tension can be maintained in steel eX- cept by a corresponding strut resistance and the main sense of my invention is to so arrange the strut members 5, thatr their strut action (viz :'-to hold the tension in reinforcements 6, while the concretey 15 sets into cohesion with said initially tension-ed reinforcements 6) may be released after concrete 15 has set into hard cohesion with the initiallytensioned reinforcements 6, and when this strut action of members 5 is so released and the strut acionof members 5 is ythereby.transferred over to concrete 15, the

a permanent live force, inside of cach unit 4, which at all times clamps concrete 15 together.

The cohesion between the hardened concrete 15 and the initiallyv tensioned reinforcements 6, besides the grip which corrugations 16 have upon concrete 15, will hold the tension in reinforcements 6, after the strut action of members is removed, because that cohesion and that grip prevent the said shrinking back of the steel moleculesin reinforcements 6, and which, in turn, brings about the permanent live force to which I have just made reference.

The importance of my invention lies in the fact, that when the pressures are acting aga-inst each of the units 4, those pressures will first have to take up, or absorb, the initial `tension inreinforcements 6, before the concrete can commence to feel those pressures. y

The cohesion of concrete 15 to reinforcement steel 6,-as well as the grip which corrugations 16 give steel 6 upon the concrete 15,-takes place throughout the whole length of reinforcement steel 6. The clamping together process of concrete 15, to which I have alluded above, therefore operates upon that part of concrete 15, which is in adherence to steel 6;-namely along the whole length of steel 6, so that the closer together reinforcement steel 6 stands, the more evenly the above referred to live force will be distributed throughout each unit 4.

5 I-Iad I left the strut action of members 5 in the finished structure, that strutv action would have prevented the reaction of the tension, in reinforcements 6, from clamping the concrete 15 together. 1

Between each of the finished units 4 I can place a suitable plastic material (properly sealed against the water) which will allow for the expansions.

Various modifications of structure may be 0 made without depart-ing from the spirit of my invention.

I claim y 1. In the construction Iof a reenforced concrete dam, the combination of the one end of 59 a reenforcement anchored to the base of a unit of said dam, said reenforcement initially tensioned by a tensioning device attached to the other end of said reenforcement, a strut member intermediate said base and said de- J vice,.concrete embedding said reenforcement, and means whereby the strut action of said member may be transferred from said member to said concrete, after said concrete has set into cohesion with said initially tensioned reenforcement.

2. In the construction of a reenforced concrete dam, the combination of the one end of a reenforcement anchored to the base of a unit of said dam, said reenforcement initially ten- 5 sioned by a device attached by removable means to the other end of said rcenforcement,

a strut member intermediate said base and said device, and concrete embedding said reenforcement, whereby the strut action of said member may be transferred from said member to said concrete, by removing said means, after said concrete has set into cohesion with said initially tensioned reenforcement.

3. In the construction of a reenforced concrete dam, the combination of the one end of a reenforcement anchored to the base of a unit of said dam, said reenforcement initially tensioned by a device attachedk by removable means to the other end of said reenforcement, a strut member intermediate said base and said device, concrete embedding said' reenforcement, and removable means isolating said member from said concrete, whereby the strut action of said member may be transferred from said member to said concrete, by removing said device and said member, after said concrete has set into cohesion with said initially tensioned reenforcement.

HENRY SORENSEN. 

